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public class FilterArrayList<T> extends
ArrayList<T>
{
/**
*
*/
private
static final long serialVersionUID = 1975316155027160540L;
private
IObjectFilter mFilter;
private
Integer[] mFilteredIndices; //过滤后的index,
public
FilterArrayList(List<T> list)
{
super(list);
}
public
FilterArrayList()
{
super();
}
public
boolean add(T object)
{<br> //如果当前list处于过滤状态,则不允许添加新的对象
if(mFilter != null)
{
return
false;
}
return
super.add(object);
}
/*<br> * 在过滤状态下,要处理一系列插入删除动作, 有待完善<br> */
@Override
public
int size()
{
if(mFilteredIndices != null)
{ <br> //此时,过滤后的index集合的大小就是整个List的大小
return
mFilteredIndices.length;
}
else
{
return
super.size();
}
}
public
T get(int
index)
{
if(mFilteredIndices != null)
{<br> //过滤状态下,转换过滤后对应的index
index = getFilteredIndex(index);
}
return
super.get(index);
}
public
void setFilter(IObjectFilter filter)
{
if(filter == null)
{
removeFilter();
}
else
{
mFilter = filter;
applyFilter();
}
}
private
void applyFilter()
{
mFilteredIndices = null;
int
size = super.size();
List<Integer> indices =new
ArrayList<Integer>();
for(int
i=0;i<size;i++)
{<br> //调用过滤接口
if(mFilter.filter(super.get(i)))
{<br> //如果返回true则保存此index
indices.add(i);
}
}
mFilteredIndices = new
Integer[indices.size()];
indices.toArray(mFilteredIndices);
}
public
void removeFilter()
{
mFilter = null;
mFilteredIndices = null;
}
private
int getFilteredIndex(int
index)
{
return
mFilteredIndices[index];
}
}
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